Joint manure fermenter may help reduce ammonia and greenhouse gas emissions

December 6, 2023

Implementing a low-emission barn system, where sludge is removed daily to be fermented and stripped, could significantly reduce greenhouse and ammonia emissions in the dairy farming sector. This is shown by a modelling study on the possibility of achieving joint mono-manure fermentation in 26 dairy farms.

Wageningen Livestock Research conducted the research at the behest of Friese Drieslag, an energy cooperation in Wijnjewoude. The model study shows that the 26 participating businesses could potentially achieve a 30-62% reduction in ammonia emissions. The greenhouse gas emissions, methane, in particular, could be reduced by as much as 78%.

These results require sludge to be removed from the barn daily and fermented after a short storage period. The digestate must subsequently be stripped. If the manure is thus processed, this group of 26 dairy farmers could be soil-bound, even without derogation. Manure need not be otherwise removed from the farmbussiness.

Moreover, assuming that RENURE fertilisers are permitted as artificial fertilisers in the future, a reduction in fertilisers of as much as 160 tonnes per annum may be achieved. RENURE (REcovered Nitrogen from MAnure) is a fertiliser gained from animal manure or digestates derived from animal manure containing nitrogen. This reduction represents €700.000 per year in savings. Finally, the central fermentation of manure and production of green gas prevents the equivalent of 1786 tonnes in CO2 emissions.

The results of this modelling study should be interpreted as a guideline to show the potentially achievable results in practice rather than as fixed data. The actual results can only be determined with certainty once a specific barn system is selected and the emissions measured in field conditions that include farm-specific characteristics.